Reaction and Diffusion Coupling on Polymer-Modified Surface: Insights from Dynamic Reaction Density Functional Theory

Polymer modification on catalyst surface is one of theimportantmeans to regulate the catalytic reaction performance. The modificationcan affect the spatial distribution and diffusion properties of reactantsand products, thus affecting the degree of matching between reactionand diffusion. Herein, a theoretical model of catalytic reactionson polymer-modified surfaces was constructed to explore the reaction-diffusioncoupling behavior. In general, the presence of grafted polymer limitsthe reaction because of the constrained diffusion by the steric effect.The long-range attraction of molecules promotes the reaction by enhancingthe adsorption of reactants into the reaction region. With the increaseof the attraction strength, the system shows an optimal grafting densitydue to the competitive results between steric hindrance and long-rangeattraction. By regulating grafting conditions (grafting density orchain length) to appropriate values, the polymer-modification canenhance the reaction efficiency with improving the consistency betweenreaction and diffusion. This work provides important insights forthe optimization of reaction efficiency by polymer modification oncatalyst surfaces.